ATLANTA, Reuters [WS] via Individual Inc. :
The largest outbreak of human monkeypox ever reported has caused more than 500 people to
become ill in the Democratic Republic of Congo, health officials said Thursday.

The Centers for Disease Control and Prevention (CDC) said children 16 and under
accounted for 85 percent of the 511 human monkeypox cases that have occurred in the former
Zaire since February 1996.

The CDC said it was the largest human monkeypox outbreak ever recorded. Five deaths
were recorded, all of them of children aged between 4 and 8.

Monkeypox is a sister virus of smallpox and is generally spread by squirrels and
monkeys in the rain forests of western and central Africa. Before the outbreak in the
Democratic Republic of Congo, cases of monkeypox in humans were rare.

Dr. Brian Mahy of the CDC's National Center for Infectious Diseases said the outbreak
does not suggest that the virus has become more virulent. ``We don't think that the virus
has changed in any noticeable way since the early 1980s,'' he said.

The increase in monkeypox cases may have occurred because of a combination of exposure
to animals and the end of smallpox vaccination programs after the illness was eliminated
in 1980. The smallpox vaccine also protected against monkeypox.

``We know that there's been a lot of rebel fighting and disturbance in that area, which
may have resulted in people going out of their houses to the bush a little bit more,''
Mahy said. ``That could provide much greater contact with the animals from which this
disease is normally acquired.''

Monkeypox resembles smallpox, causing fever, swollen lymph nodes, respiratory illness
and pus-filled blisters on the skin. There is no cure for the still rare and generally
nonfatal viral disease, which generally lasts about a week.

Mahy said the outbreak of monkeypox does not suggest a resurgence of smallpox, which
was eliminated worldwide in 1980. ``It is clearly quite different from smallpox, and it is
not the sort of virus that could mutate into smallpox. There are major, major differences
between the two,'' he said.

Last week the World Health Organization said it was not urging the reintroduction of
smallpox vaccination programs in Africa to prevent monkeypox. Instead, it recommended
limited contact with animals caught in the wild and with people who are believed to have
become infected.